Raincoast biologist Misty MacDuffee joined Mark Brennae on CFAX 1070 to talk about the Fraser River and the fish that rely on its distinct and interconnected habitat. The Fraser Estuary supports more than 100 species that are recognized as “at-risk” (threatened, endangered or of concern) either provincially or federally.1
Misty MacDuffee is part of a team of researchers working in the Fraser River estuary to try to understand how habitats within the estuary work together to support these species.
They have a paper that was recently published in Marine Ecology Progress Series, with lead author Lia Chalifour. Factors like salinity, oxygen and temperature have local and seasonal influences on fish presence and life stages within each habitat, but habitat type was the most important factor for determining where salmon were caught.
Importantly, as an estuary, this is where fresh water from the Fraser mixes with saltwater from the Pacific; it’s a critical place for salmon during their transition from being a freshwater fish to a marine fish. When juvenile salmon move from the river into the estuary they undergo osmoregulation.
The development and changes that have taken place over the last century in the Fraser River estuary have been significant.
“Now that we know how important these habitats are, and how important the connectivity between those habitats is, we need to reconsider the decisions that erode the quality of that habitat, or remove habitat, for what are increasingly becoming threatened and endangered salmon from the Fraser River.”
Listen to the whole interview.
“Ultimately the decisions impacting the Fraser River estuary are social decisions. The implications of human activity like development, agriculture, port expansion on salmon are critical. So we need to, collectively, prioritize decisions on our footprint, and support the resilience of salmon populations. Habitat is critical. We know that, and this is another study that demonstrates that. The estuary has distinct habitats. They’re interconnected. And the estuary, as a whole, is critical to salmon.”
“Collectively we need to say that the priority now needs to be on the resilience and survival of species and habitat that still exist. We can’t keep going down this road, so the public needs to get more involved in decision making.”
- Mark also asked Misty about the land slide that occurred in the Fraser River canyon earlier this year. Chinook, sockeye, coho and pink salmon have been prevented from swimming upstream of this barrier. It has been difficult for humans to access this area to help salmon to get through. The loss of spawning salmon will have a significant legacy effect on future populations. ↩